POJ 1273

来源：互联网发布：生产者消费者模式 php 编辑：程序博客网时间：2024/04/19 14:30

#include <stdio.h>#include <string.h>int map[201][201], flag[201], queue[1000], pre[201], m, yes, min, searchmin[201];int find_min(int a, int b){    return a>b?b:a;}void bfs(){    memset(flag, 0, sizeof(flag));    int i, j, head, tail,  x;    searchmin[1]=100000;    head=tail=0;    queue[0]=1;    yes=0;    flag[1]=1;    while(head<=tail)    {        x=queue[head];        for(i=1; i<=m; i++)            if( (!flag[i]) && map[x][i])            {                flag[i]=1;                searchmin[i]=find_min(searchmin[x], map[x][i]);                queue[++tail]=i;                pre[i]=x;                if(i==m)                {                    yes=1;                    goto X;                }            }        head++;    }    X:    min=searchmin[m];    if(!yes) return;    x=m;    while(pre[x])    {        map[ pre[x] ][x]-=min;        map[x][pre[x]] += min;        x=pre[x];    }}                int main(){    int n, i, ans;    pre[1]=0;    while(scanf("%d%d", &n, &m)!=EOF)    {        ans=0;        memset(map, 0, sizeof(map));        for(i=0; i<n; i++)        {            int x, y, xy;            scanf("%d%d%d", &x, &y, &xy);            map[x][y]+=xy;        }        while(1)        {            bfs();            if(!yes)break;            else ans+=min;        }        printf("%d\n", ans);     }    return 0;}

虽然有些地方还是不太明白~~Orz